linux-kernel - [PATCH v0 25/42] arch/um: Check notifier registration return value

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20211108101157.15189-26-bp@alien8.de>
Date:   Mon,  8 Nov 2021 11:11:40 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     LKML <linux-kernel@...r.kernel.org>
Cc:     linux-um@...ts.infradead.org
Subject: [PATCH v0 25/42] arch/um: Check notifier registration return value

From: Borislav Petkov <bp@...e.de>

Avoid homegrown notifier registration checks.

No functional changes.

Signed-off-by: Borislav Petkov <bp@...e.de>
Cc: linux-um@...ts.infradead.org
---
 arch/um/drivers/mconsole_kern.c | 6 ++++--
 arch/um/kernel/um_arch.c        | 5 +++--
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c
index 6ead1e240457..ceea940c0aa0 100644
--- a/arch/um/drivers/mconsole_kern.c
+++ b/arch/um/drivers/mconsole_kern.c
@@ -856,8 +856,10 @@ static struct notifier_block panic_exit_notifier = {
 
 static int add_notifier(void)
 {
-	atomic_notifier_chain_register(&panic_notifier_list,
-			&panic_exit_notifier);
+	if (atomic_notifier_chain_register(&panic_notifier_list,
+					   &panic_exit_notifier))
+		pr_warn("UM console panic notifier already registered\n");
+
 	return 0;
 }
 
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 54447690de11..6c0e562ff0b7 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -255,8 +255,9 @@ static struct notifier_block panic_exit_notifier = {
 
 void uml_finishsetup(void)
 {
-	atomic_notifier_chain_register(&panic_notifier_list,
-				       &panic_exit_notifier);
+	if (atomic_notifier_chain_register(&panic_notifier_list,
+					   &panic_exit_notifier))
+		pr_warn("UM panic notifier already registered\n");
 
 	uml_postsetup();
 
-- 
2.29.2